Two very charming (and not too expensive) roguelite games I haven't seen in the comments yet are Blazing Beaks and Dicey Dungeons... I played them on the Switch, but I'm sure they can also be purchased through Steam etc.
In Blazing Beaks, you play different birds with different characteristics and shoot your way through various levels while collecting useful items and annoying debuffs/handicaps like for example, "you cannot shoot while you run" or "every coin you collect deals 1 damage" These debuffing items are the core mechanic - you can collect and exchange them for some really nice stuff that helps you in the long run. Lovely pixel art and really great as a 2 player local coop!
Dicey Dungeons is a little hidden gem where you play as a little dice character and have to fight turn-based encounters in order to escape the dungeon of Fortuna. The mechanics are quite simple: Roll some dice and use them to deal out damage, shield yourself, poison your enemy etc. For example, you might start with a weapon that says "deal X damage points", so if you roll a 4 and insert it into the weapon slot, the enemy takes 4 damage points. There are a handful of different characters that all work differently (my personal favourite is the roboter where you have to gamble if you want to roll another dice to use in attacks, because once you roll too high, you lose the dice you already rolled for this round). Also, each character has a handful of different modes/rule sets so it doesn't get repetitive. Bonus points for a pretty art style, charming enemies and some catchy tunes!
Btw, Hollow Knight is not a roguelite but a metroidvania since the levels, items and encounters are not randomized and unique in every play through, but it is absolutely worth playing!